Crashlytics, a Cambridge-based startup that helps developers understand why their mobile apps are crashing, has just beat out an unnamed competitor to acquire the bootstrapped startup called FireTower.app. The FireTower solution was focused not on mobile apps, but on web applications, allowing developers to find javascript errors in their websites. Now, Crashlytics will be repurposing that technology for use by mobile web developers.

Terms of the acquisition were not disclosed, but Crashlytics co -founder Wayne Chang says the other side is “very happy.”

The deal was not for the Boston-based FireTower.app team, a small group led by Aaron White, now the co-founder of VC-backed educational-focused startup, Boundless – it was for just the technology itself. White will be helping Crashlytics during the transition period, however.

Chang explains that Crashlytics was already interested in adding to its core product line with a solution for mobile web developers, or those whose native apps use the mobile web in some way, but building what they wanted themselves would have taken six months. They just wanted to get it out there as fast as possible, Chang says.

The FireTower.app solution will serve as the base for Crashlytics new mobile web-focused feature set. To start, the technology will now allow developers the ability to de-minify their javascript code in their mobile web apps (meaning translating errors back into a plain language that a developer understands). It’s a hard problem to tackle, but one that developers will be really grateful for.

Interestingly, the acquisition comes only a few months after Crashlytics itself decided to turn down its own offer to be acquired by another company focused on web-related services for developers, but with an itch to move into mobile. “We thought we could still realize more value…for our users, shareholders and stakeholders,” says Chang as to why the company turned them down. “We want to build the best company we can, and the best products for our users,” he added.

Currently the Crashlytics error-reporting solution is in a private beta and is now running on approximately 100 million devices. Thousands of developers are on the waitlist and Chang says they expect to see hundreds of millions of devices using the solution when the beta ends. (That’s expected to happen sometime later this year.)

Crashlytics is backed by $6 million in funding (its $5 million Series A was over-subscribed, Chang notes). Their team of 11 is now moving into new office space in Cambridge and contemplating setting up additional offices in the San Francisco Bay/Silicon Valley area. By year-end, they expect to have 20 to 25 people at the company in total.

The new features provided by the FireTower.app solution are still in the process of being added to the Crashlytics core product now, but the plan is to have them go live in the next month or so.